Decolourisation of real textile waste using electrochemical techniques: Effect of electrode composition

• Published in: Journal of hazardous materials 2008-08, Vol.156 (1), p.170-177
• Main Authors: Malpass, G.R.P., Miwa, D.W., Machado, S.A.S., Motheo, A.J.
• Format: Article
• Language: English
• Subjects: Anode effect; Anodes; Applied sciences; Carbon; Chemical engineering; Color; Colors (materials); Colour; Colour removal; Composition effects; Consents; Decolourisation; Degradation; Effluents; Electrochemical degradation; Electrochemistry - methods; Electrodes; Electrolysis; Energy consumption; Exact sciences and technology; General purification processes; Indicators and Reagents; Industrial Waste; Oxidation; Pollution; Reactors; Spectrophotometry, Ultraviolet; Textile effluent; Textile Industry; Textiles; Tin dioxide; Tin oxides; Titanium; Wastes; Wastewaters; Water treatment and pollution
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2007.12.017

The present paper presents the study of the decolourisation of real textile effluent by constant current electrolysis in a flow-cell using a DSA ® type material. The effect of using different anode materials (Ti/Ru 0.3Ti 0.7O 2; Ti/Ir 0.3Ti 0.7O 2; Ti/Ru X Sn 1− X O 2, where X = 0.1, 0.2 or 0.3) on the efficiency of colour removal is discussed. Attempts to perform galvanostatic oxidation (40 and 60 mA cm −2) on the as-received effluent demonstrate that colour removal and total organic carbon (TOC) removal are limited. In this case the greatest degree of colour removal is achieved when anode containing 90% SnO 2 is used. If the conductivity of the effluent is increased by adding NaCl (0.1 mol L −1) appreciable colour/TOC removal is observed. The efficiencies of colour and TOC removal are discussed in terms of the energy per order ( E EO/kW h m −3 order −1) and energy consumption ( E C/kW h kg −1 TOC), respectively. Finally, the extent of colour removal is compared to consent levels presented in the literature.